Photographic type composition



Oct. 16, 1962 R. c. O'BRIEN PHOTOGRAPHIC TYPE COMPOSITION 4 Sheets-Sheet1 Filed March 12, 1958 mi m: 92 E wk 8s R on com mmwozmh INVENTOR.RICHARD c. O'BRIEN mmoQE.

ATTORNEYS Oct. 16, 1962 R. c. OBRIEN PHOTOGRAPHIC TYPE COMPOSITIONbeets-Sheet 2 Ix 8- &

Filed March 12, 1958 INVENTOR RICHARD c. O'BRIEN ATTORNEYS 4"Sheets-Sheet 3 Filed March 12, 1958 RESET FROM SELECTOR RICHARD c.O'BRIEN @WMW ATTORNEYS R. c. OBRIEN PHOTOGRAPHIC TYPE COMPOSITION Oct.16, 1962 ms 31% 4 R. N m 0 E 4 N m m m m w w w law M A w R m 4 l R I w Mmowoudw Filed March 12, 1958 \m k 9m 3m Smmm 8% :m mvm United StatesPatent 3,059,219 PHOTOGRAPHIC TYPE COMPOSITIO Richard C. OBrien,Cleveland, Ohio, assignor to Harris- Intertype Corporation, Cleveland,Ohio, a corporation of Delaware Filed Mar. 12, 1958, Ser. No. 720,840 8Claims. (Cl. 340-1461) This application relates to photographic typecomposition, to phototypesetting machines and the like, especially toapparatus for selecting a desired character on a matrix bearing aplurality of characters as portions of difierential light transmittingability, and to the selection of specific locations on a matrix or thelike for similar purposes.

The present invention is particularly suitable for rapid determinationof a desired location on a matrix or similar member bearing distinctivecode indicia. In accordance with the invention the code indiciacharacteristic of each possible location is compared with the desiredcode in a selector system, and when the code indicia corresponding tothat in the selector is located, an output sign-a1 is immediatelyprovided which may be used, for example, to eifect photography ofmaterial located on the matrix in predetermined relation to the locatedcode indicia. Thus, there is no need to work from a reference point onthe matrix or other code bearing member, and more than one location maybe located on the matrix during each cycle of scanning of all the codeindicia.

Accordingly, the primary object of this invention is to provide animproved system for scanning a plurality of code indicia on a matrix orlike member and for selecting desired locations on the matrix inpredetermined succession, as indicated by the location of code indiciaon the matrix corresponding to a selected code, by instantaneouslyindicating a coincidence between the selected code and its correspondingindicia on the matrix.

A further object of this invention is to provide a system for locating aselected binary code indicia on a member bearing a plurality of suchindicia, by comparing each of the indicia on the member with theselected code, digit by digit, until the coinciding indicia is locatedon the member.

Another object of the invention is to provide such a coincidenceresponsive system wherein the scanning or reading of each indicia on themember is performed independently of the other indicia thereon,providing for a number of possible coincidences during each cycle ofscanning all the indicia on the member.

An additional object of the invention is to provide an improvedcharacter selecting system for phototypesetting apparatus wherein thecharacter identifying code indicia for each character is independent ofother indicia and occupies a zone on the character matrix of minimumradial width.

A further object of this invention is to provide such an improvedcharacter selecting system wherein coincidence between the selectingcode and the identifying code on the matrix will produce immediately anoutput signal effective to energize or actuate the associated high speedphotographic equipment and record the character identified with suchcode.

Another object of this invention is to provide a system for locating aselected binary code number on a matrix or similar member having aplurality of different code numbers recorded thereon, in which systemall of the code numbers or indicia on the matrix are scanned in cyclicfashion and each compared digit by digit with the selected code numberto seek coincidence between each digit of the selected number and eachdigit of the code indicia on the matrix, and wherein discriminatingapparatus receives signals for digit by digit coincidences ice such thata noncoincidence between any digit of the selected number and the codeindicia being scanned will cause the discriminating apparatus to becomeout of phase with the scanning cycle, thereby providing that an outputindicating the location of the selected number can occur only, andimmediately, when complete digit by digit coincidence occurs in thediscriminating means.

In the drawings FIG. 1 is a schematic diagram of one selector systemprovided by the invention;

FIG. 2 is a fragmentary view on an enlarged scale of the characterbearing matrix shown in FIG. 1;

FIG. 3 is a diagrammatic illustration of another embodiment of theinvention;

FIG. 4 is a detail diagram of coincidence circuits employed in theapparatus of FIG. 3; and

FIG. 5 is a diagrammatic illustration of a further embodiment of theinvention.

Referring to the drawings, which illustrate preferred embodiments of theinvention, and particularly referring to FIG. 1, there is shown a matrixdisk 10 which is mounted for rotation about its axis 12, and which bearscharacters 15 located at a common radial distance from the axis ofrotation 12. These characters are defined by suitable pants ofdiiferential light transmitting ability so that a light beam passingnrom the spark gap 17 through condensing lens 18 will be formed, onpassage through one of such characters, to provide an image bearinglight beam which then passes through a suitable focusing and sizecontrolling optical system 20 onto a photosensitive record materialwhich may be carried, for example, upon the drum 22.

Relative movement between the light beam from spark gap 17, which is ofrelatively high intensity and short duration, may be provided byrotating the disk, thus bringing successive characters into alignmentwith the possible path of the light beam, and by properly controllingthe flashing of the light source or spark gap 17 desired characterimages may be projected onto the light sensitive material for recordingin succession thereon. Suitable apparatus for spacing successivelyprojected character images may be provided, for example as described indetail in the copending application of Frederick J. Hooven and RichardC. OBrien, Serial No. 661,633, filed May 27, 1957, now Patent No.2,966,835.

The present invention relates particularly to apparatus for determiningthe instant when a selected character, identified by a suitable binarycode number for example, is properly aligned with the optical system forphotographing that character. In accordance with the invention eachcharacter is identified by a binary code number which is recorded asindicia on matrix disk 10 in predetermined spatial relation with respectto the character which it identifies. For purposes of example the codeis illustrated as a seven digit binary code.

Referring to FIG. 2, and using as an example the code number 1000000 ascorresponding to the character A, the mark 30 indicative of a "1 in thecode number is located at a characteristic radial distance from thecenter of disk 10. Immediately following this mark are six further marks32 which all fall on a common radius from the center of disk 10,different from the radius upon which mark 30 is located. In other Words,all marks representing lf are at a different distance from the center ofrotation from the marks representing 0. The last of these seven marks,identified as 32, is located in predetermined spaced relation withrespect to the character A, and thus the position of mark 32' may beused as an indication of the proper alignment of the character A withrespect to the optical system.

In similar fashion, the code for character B may be 0100000, and thecode for character C may be 1100000,

and so on, as will be apparent from an inspection of FIG. 2. Each set ofcode marks is set ofi from adjacent sets by an elongated mark 35 whichextends through both of the radial zones occupied by the l and marks 30and 32. All of these marks preferably are made in such a fashion thatthey are of differential light transmitting ability with respect to thedisk background. For example, the disk may be opaque and the markstranslucent, or vice versa.

Again referring to FIG. 1, the areas of the disk in which these tworadial zones are located are illuminated by lights 38 from which rays oflight pass through suitable lenses 39, and these light ray areinterrupted by the differential light transmitting parts in the two codezones to provide pulse generating means. On the other side of disk thereis mounted a first photocell PC which is aligned with the zone on thedisk in which the marks appear, and thus pulses sensed by PC areindicative of a l in a particular identifying code. In like fashionphotocell PC is located opposite the zone bearing the zero marks 32, andthus pulses sensed by PC are indicative of 0 in the code. The output ofPC passes through line 40 to a suitable trigger circuit 42 and theoutput of the trigger circuit is connected through line 43 to adiscriminator pentode 45, specifically to the first or control grid 456thereof through a condenser 4-6. This grid is normally biased to cut-oilpotential through resistor 47 which is connected to a suitable source ofnegative po tential, While the cathode 450 is connected to ground asshown.

In like manner, the output of photocell PC is connected through line 51)to a trigger circuit 52 and the output of this circuit passes throughline 53 to the control grid 55G of pentode 55 through a condenser 56.Also in like manner the grid 55G is biased negative through resistor 57.

The plate circuits of pentodes 45 and 55 are connected to a commonoutput 60 which provides an input to a bi-stable flip-flop circuit 62.Thus, a pulse from either of these pentodes, due to momentaryconductances thereof, will cause flip-flop 62 to reverse its state.

Referring to the upper right portion of FIG. 1, a suitable selectorcircuit is designated generally at 65 and may comprise any suitablecircuit for retaining temporarily a binary code number which identifiesa character to be selected from disk 10. The selector circuit mayinclude means for receiving an input from any suitable coding device,and thus may operate directly from a keyboard, as in the copendingapplication of Frederick J. Hooven and Richard C. OBrien, now UnitedStates Patent No. 2,846,932, issued August 12, 1958, and assigned to thesame assginee as this application, or the selector may operate from anysuitable coded record such as a punch tape or magnetic tape.

The output 66 of selector circuit 65 passes to a bank of bi-stableselector fiip-fiop circuits 7076 which are independent of each other andare individually under the control of the selector output. Thus each ofthe fiip-fiops 70-76 may be set at its 0 or 1 state by the selectorcircuit independently of the others. Corresponding to the flip-flops70-76 there is a bank of dual triodes 80-86, and the first plate of eachof these dual triodes, designated 80P 81P etc., are connected to acommon output line 88 which is in turn tied to a voltage dividingcircuit comprising a load resistor 90, a dividing resistor 92, and anegative biasing resistor 93. As shown in the drawing resistor 90 isconnected on one side to the plate load line 88 and to dividing resistor92, and on its other side to a B+ supply which may conveniently beapproximately +25 V. The negative biasing resistor 93 is connected onone side to a negative supply, for example -75 v. as indicated, and atits other side to dividing resistor 92 and to output line 95 whichextends to grid 55G of discriminator pentode 55.

The other or second plates of the dual triodes 80-86 designated 8018115, etc., are connected through a common plate line '98 to anothervoltage dividing circuit in cluding resistors 100, i102, and 103 whichare connected in the same fashion as described above in connection withthe voltage divider circuit 90, 92, 93. An output line 105 is connectedinto this voltage dividing circuit between resistors 102 and 103 andextends to the second control grid 456 of discriminator pentode 45.

Each of the flip-flop circuits 70-7 6 has two output lines which areconducting or nonconducting depending upon the state of the associatedflip-flop circuit. For example, the bi-stable fiipl-fiop 70 has anoutput line 700 which is biased positive if the flip-flop is in its 0state and a second output 701 which is biased positive if flip-flop 70is in its "1 state. Line 701) is connected to the first control grid 866of tube 80, and similarly line 701 connects to the second grid W6 Inlike fashion, the output lines 710, 711; 720, 721; 730, 731; 740, 741;750, 751; and 760, 761 are connected to the grids 816 81G 82G 82G etc.,and thus the grids of the dual triodes will be set up in accordance withthe state of the individual bi-stable flip-flops 70-76. Referring to thelower right portion of FIG. 1, a beam switching tube is illustratedschematically. This tube is of the type manufactured by BurroughsCorporation and as disclosed, for example, in United States Patent2,721,955. It will be understood that for purposes of illustration themeans for creating the magnetic field about this tube has not beenshown. Such means is well known in the art and is disclosed in saidPatent 2,721,955.

Beam switching tube 110 includes a common cathode 112 which may beconnected to a negative source of potential, for example -75 v., and aplurality of target elements 120429. For each target there is acorresponding beam deflecting element or spade -139, and correspondingbeam switching elements or grids -149. The switching grids 140, 142,144, 146 and 148 are wired to a common input line 152 and throughcondenser 153 to one side of the bi-stable flip-flop 62 The odd numberedswitching grids 141, 143, 145, 147 and 149 are carried through a commoncontrol line 156 which is connected through condenser 157 to the otherside of flip-flop 62. The remainder of circuit 158 constitutes aconventional switching circuit or network for providing proper bias tothe odd or even numbered switching grids.

All of the spade or switching elements with the exception of the firstspade 130 are connected to a common load line 160, through suitableresistors as shown, which is in turn connected through load resistor 162to ground. Thus, the beam switching tube operates on the relatively lowpotential difference of less than 75 v. The first spade element 130 isconnected to the load line through an additional resistor-capacitornetwork 163 which receives a resetting impulse from a suitable resetcircuit 165. An impulse from this circuit at any time will cause thebeam of electrons to be clamped to the first target element 120,ignoring the others, by lowering the potential of all spade elementsbelow cut-off potential, after which all of the spades :131-139 willrise to ground potential before spade 130, due to the network 163,thereby forming the beam on the first target 120. The last two targetelements 128 and 129 are not used in this circuit, and therefore theyare connected directly to ground through suitable biasing resistors 167.

The spade element 137 is connected directly to an output line whichextends to the spark control unit 172 governing the energization of theelectrodes 17. The pulse that appears at spade element 137 is fastrising and thus provides an almost instantaneous signal to spark controlcircuit 172 when the electron beam is switched for the seventh time, tothe target element 127. This target element is connected directlythrough output line 175 to an amplifier 176 which in turn supplies areset pulse through reset line 177 for resetting all of the flip-flopcircuits 70- 76 to a common state, for example to 0." By providing sucha separate reset output to the selector flip-flops, the reset circuitsare isolated from the main output line 170 and therefore do not tend toload and possibly weaken the main output pulses to the spark controlunit.

Each of the first seven target elements 120-126 is connected throughrespective output lines 180-186 to the cathodes of the dual tridoes80-86, each of these output lines 180-186 from the beam switching tube110 thus controlling the operation of a corresponding dual triode 80-86.

A suitable and gate circuit 190 is connected to receive input pulsesfrom both of the photocell trigger circuits 42 and 52 through inputlines 102 and 103. As is characteristic of such and gate circuits, whena pulse is received from both of the trigger circuits an output pulsewill pass through output line 195 to reset circuit 165.

The operation of the system is as follows. Assuming for purposes ofexample that it is desired to select and photograph the character A, andthat as described in connection with FIG. 2 the code for A is 1000000.This code is fed to the selector circuit 65 which in turn sets up theflip-flops 7076 so that the first flip-flop 70 assumes the positioncorresponding to 1 and the others are in their state. Thus, the grid 80Gis biased positive. Assuming further that the elongated reset mark 35(FIG. 2) immediately preceding the code indicia identifying character Ahas just passed the photocells PC and PC then the and gate circuit 190has passed a reset pulse to reset circuit 165 which in turn has causedthe electron beam in beam switching tube 110 to reset and be clamped tothe first target element 120, thus in effect connecting the cathodes ofdual triode 80 to the 75 v. supply.

The grid 806 has been biased positive while grid 80G remains negative,as explained above, and thus the right hand side of tube 80 conducts andan output signal is passed through line 98 to the voltage dividingnetwork including resistor 100, 102 and 103, thereby bringing the outputline 105 to a higher or more positive potential. At the same time, therelative movement between matrix disk 10 and the reading means (providedby the photocells PC and PC is continued. Preferably, this relativemovement is continuous and is provided by rotating the matrix diskrelative to the photocells which are supported in a fixed position.

Thus, referring to FIG. 2, the first or 1 mark 30 causes photocell PC totransmit a pulse to its corresponding trigger circuit 42, and throughline 43 and condenser 46 to bias grid 45G momentarily positive. It willbe recalled that there is an output signal in line 105 which isconnected to grid 45G and therefore the discriminator pentode 4 5conducts, and an outer pulse is passed through line 60 to the bi-stablecontrolling flipflop circuit 62. The signal through line 60 is in thenature of a pulse only, since although the grid 45G is biasedmomentarily positive, the positive bias through condenser 46 fromphotocell PC is a sharp pulse, and thus grid 456 is biased positive onlyfor a short duration.

Going on to the next selector flip-flop 71, its corresponding comparatortriode 81, and the corresponding target element 121, the pulse tocontrol flip-flop 62 will cause the electron beam in beam switching tube110 to shift to the second target 121, due to the change in state offlip-flop '62 which switches the polarity of the switching grids througha conventional switching circuit or network 158. This causes the evennumbered grids to be biased negative and to place a positive bias on theodd numbered grids through line 156. The cathodes of tube 81 are nowconnected to the negative potential through the beam switching tube, andsince in the example flipflop 71 has been set to read 0, the grid 81Gwill be biased positive causing a signal to pass through line 88 to thevoltage divider circuit including resistors 90, 92 and 93, and an outputsignal will be passed through line 95 to the grid 55G of thediscriminator pentode 55.

Noting from FIG. 2 that the next code mark in the code identifyingcharacter A is a 0 mark, then the pulse from photocell PC through itstrigger circuit 52, and through the output line 53 and condenser '56,will cause grid 55G to be biased positive for a period sufficient toemit a further pulse through output line 60 to the control flip-flopcircuit 62. Accordingly, the electron beam in the beam switching tubewill advance or step to the next target element 122 and the samesequence just described will be repeated.

Thus, the beam switching tube 110 in combination with the followingaction of the dual triodes -86, provides a means for scanning the codenumber set up in the flip-flop circuits 70-76 digit by digit, and forproviding for each such flip-flop circuit an output signal in eitherline or line 105, characteristic of whether the digit in the flip-flopbeing examined is an 0 or a 1.

At the same time, the photocells PC and PC are scanning or reading thecode indicia on the disk to de termine, digit by digit, thecharacteristic code number which is passing these photocells between twoconsecutive reset marks 35. These marks index beam switch tube with thephotocells or reading means, and thus if there is a coincidence betweenthe first digit of the code number being read and the first digit in thenumber set up in flip-flops 70 76 by the selector, then an output pulsethrough line '60 causes the controlling flip-flop 62 to step theelectron beam to the next target 121. If the second mark of the codeindicia being read coincides with the set of the second flip-flop 71again the discriminator circuits (pentodes 45 and 55) provides astepping pulse to step the beam to the third target 122, and so on.Thus, since the pentodes 45 and 55 both have their place circuitsconnected to the flip-flop 62, and since the grids 45G and 55G arealternately biased positive, this circuit tends to advance or step thebeam switching tube 110 in phase with the rate at which the readingmeans (photocells PC and P0 scans or reads the digits of the code data.If at any time during this comparing operation, which occurs over andover for each identified code indicia on the matrix disk, there is anoncoincidence, then the beam switch tube 110 does not advance for thatone step and lags behind, or falls out of phase with, the code beingread or scanned. In order to have an output through line which willtrigger the spark control circuit 172, the discriminator circuits mustfind seven coincidences, or in other words it must find the code numberset up by the selector by comparing each digit thereof with each digitof the code indicia being scanned.

Assuming that coincidence is found, then the electron beam will switchto the eighth position, target 127, and the sharp or fast rising pulsereferred to above will pass from through line 170 from spade 137 to thespark control circuit 172. Accordingly, there is no rough and finecontrol as heretofore employed, but instead the present inventionprovides for comparison of the desired code number with all of the codeindicia on the matrix disk, each independently of the other, and oncethe code on the disk is found that coincides with the code set up in theselector, the light source or spark is fired immediately, or within avery short predetermined interval which is independent of. any finecontrol, to photograph the corresponding selected character. At the sametime, the slower rising pulse that appears at target 127 will passthrough line and amplifier 176 to erase from the flip-flops 7076 thecode number which has just been located, setting these flip-flops to abasic position and preparing them to receive a further code number toselect the next desired character. It will be noted that the abovedescribed apparatus is independent of any index or basic position on thematrix disk, and thus the system is capable of selecting a number ofcharacters during each cycle of relative movement between the matrixdisk and the code reading means and the optical system, within thelimits, of course, of the system to accept new selection code numbersand to reset itself.

Another form of apparatus in accordance with the invention is shown inFIGS. 3 and 4. Since the matrix disk, optical and recording system, thereading means, and the character selector are all the same as in FIG. 1,like reference numerals have been applied to these parts. The characterselector circuit 65 is connected through its output 66 to set up in thebi-stable flip-flop circuits 210-216 the binary code number which it isdesired to locate'on the matrix. Each of these flip-flop circuits mayinclude the conventional Eccles-Jordan circuit details of which areshown for flip-flop 210 of FIG. 4.

This circuit includes the dual triode 217 of which one side or the othermay be conducting, depending upon the state in which the circuit is set.Accordingly, as is Well known in the art, grid 217G may be biasedpositive when the left side of the tube is conducting, indicating astate of l for the flip-flop, and conversely grid 217(3 will be biasedpositive when the flip-flop is in its state. The flip-flop circuit maybe set up by a pulse from control tube 220 which may in turn becontrolled from the selector circuit 65 (for example as disclosed incopending application Serial No. 640,741, filed February 18, 1957}.

The controlling outputs of the flip-flop 210 (and likewise similarly forthe flip-flops 211-216) are through lines 222 and 224 which are tieddirectly to the two grids of tube 217 and are biased accordingly. Thecomparing circuits are designated generally in FIG. 3 by the referencenumerals 230-236, and each of these is coupled to a correspondingflip-flop 210-216 respectively in the same manner as shown in FIG. 4.Accordingly, the comparing or discriminating circuit 230 includes a pairof pentodes 240 and 242. For purposes of illustration the screen gridshave not been shown in the drawings, since they form no part of thecontrol of these tubes. A common plate output line 245 is connected toall of the plates of these discriminating pentodes in each of thediscriminating circuits 230-236, and this line leads to the regulatingor beam switching bi-stable flip-flop circuit 250 (FIG. 3).

Line 222 is connected to one control grid 240(3 of tube 240, andsimilarly line 224 is connected to grid 242G of tube 242. The othercontrol grids 240G and 242G are similarly biased negative throughbiasing resistors 24-3, and grid 240G is connected to receive a pulsethrough condenser 252 from the photocell trigger amplifier 42 which inturn receives pulses from photocell PC In a similar manner grid 2426 isconnected to receive pulses from PC through trigger amplifier S2 andcoupling condenser 253.

A beam switching tube 260 is provided, having its beam switching circuit262 under the control of flip-flop 250, as shown in FIG. 1, so thatevery pulse fed through line 245 results in a switching action withinflip-flop 250, which in turn changes the bias on the grid elements270-279 to step the electron beam successively to the target elements280-289. Each of the beam deflecting spade elements 290-299 is connectedthrough a corresponding resistor to ground. The first seven targetelements 280-286 are connected to the seven comparing outputs 300-306which in turn lead to the respective comparing or discriminatingcircuits 230-236, and in each instance the corresponding line from thebeam switching tube 260 is connected to the cathodes of both thediscriminating pentodes within that discriminating circuit, as shown inFIG. 4.

Referring to FIG. 3 the outputs of both trigger amplifiers 42 and 52 areconnected through lines 308 and 309 to a conventional and gate circuit310, the output of which is fed into a suitable phase inverter 312, andthe output 313 of the phase inverter leads to a typical reset circuit315 for the beam switching tube, and through branch line 3 16 the outputof the phase inverter operates to reset flip-flop 250 to a desiredstate. The output 318 of reset circuit 315 is connected through thecondenser resistor network 319 to the spade elements of the beamswitching tube for resetting the electron beam to the first targetelement 280, and operates by lowering all spades to below apredetermined cutoff potential. The spade element 280 is slower toreturn to B+ potential, due to the capacitance 319" in its B+connection, and this causes the electron beam to form on the firsttarget 2 80.

The operation of this embodiment of the invention is generally similarto that of the system previously described. A desired code number is setinto the flip-flops 210-216 by the character selected, and theconnections between these flip-flops and the discriminating circuits230-236 operate to bias positive one or the other of the control grids240G or 242G in the corresponding discriminating circuit, thus preparingone or the other of the discriminating tubes 240 or 242 for conducting.With the beam switching tube in its first position the cathodes of thediscriminating tubes in circuit 230 are connected to a negative voltage,and a pulse is received from one or the other of the photocells PC or PCin scanning the first digit of a complete code indicia on the disk.

Assuming the same example as used before, 1000000 identifying characterA, then the pulse through condenser 252 would momentarily bias grid 240Gpositive, and since flip-flop 210 was set up to its 1 state, grids 217Gand 2406 would be biased positive and an output pulse would appear inline 245, passing through the coupling condenser 320 to flip-flop 250.This in turn would cause the advance of the electron beam in beamswitching tube 2&0 to the next target element 281, and the samecomparison would be made between the second digit of the code and thecode digit in flip-flop 211. If a coincidence is found then a furtherpulse will pass through output line 245 to fiip-flop 250, and so on.

However, if in any one of the discriminating circuits 230-236 a pulsefrom the photocell reading means enters from one photocell while theopposite discriminating pentode is set up to conduct by thecorresponding selector tip-flop, or in other words if there is anoncoincidence, then the beam switching tube 260 will fall behind or outof phase with the matrix, and the required seven output pulses throughline 245 will not be obtained. Accordingly, the electron beam will notreach the eighth target element 207. If, however, there is a completedigit by digit coincidence then the beam will clamp to this target and apulse will pass through output line 325 to the spark control circuit172, causing a spark between the electrodes 17 which will illuminate thedesired selected character. At the same time a pulse will be passedthrough line 327 to clear the selector flip-flops 210-216 preparatory tosetting up a new code number therein by the selector circuits.

A further modified form of apparatus is illustrated in FIG. 5, whereagain the same reference numerals" as in FIG. 1 have been applied to thecommon parts such as the matrix disk, optical and recording systems, thecode reading means, and the character selector. The output of selectoris connected through line 66 to control individually the setting ofseven bi-stable flip-flop circuits 410-416, and each of these flip-flopsis tied to a corresponding discriminator circuit 430-436 which is of thesame type, and is connected to its corresponding flip-flop, in the samemanner as shown in FIG. 4 and disclosed in the accompanying descriptionabove.

In similar fashion the outputs of trigger amplifiers 42 and 52 areconnected through lines 437 and 438 to each of the discriminatorcircuits. An or gate circuit 450 is connected to receive pulses fromeither of the trigger amplifiers 42 or 52, and as its name implies, thiscircuit passes a pulse from either of the photocells PC or PC through adelay circuit 452 to its output line 453 which feeds the pulses to aregulating bi-stable flip-flop circuit 455. Opposite sides of thisregulating flip-flop are tied through a conventional switching network457 to the odd and even numbered switching grid elements 460-469 of abeam switching tube 458. The target elements 470-476 of tube 458 areconnected to the discriminating circuits 430-436, to provide forsequential activation of these discriminator circuits to compare thecode set up in the selector circuits with the code indicia read from thematrix disk 10.

An and gate circuit 485 receives pulses from both the photocells PC andP but of course passes a pulse through its output 486 only when theelongated or reset marks 35 (FIG. '2) pass both of the photocells. Suchan output pulse passes through a phase inverter 487 into an output line490 which is tied to the reset circuit 492 for beam switching tube 458,as well as to a reset line 493 for regulating flip-flop 455. Thus, apulse from and gate 485 resets the regulator flip-flop 455 to apredetermined state, and also resets beam switching tube 458 to directthe electron beam to the first target element 470.

The output of the discriminator circuit 430-436 is a common plate line500 which is connected in parallel to all the plate circuits of all ofthe pentodes in the discriminator circuits, in the same manner as line245 in FIGS. 3 and 4. A further beam switching tube 505 is provided,operating between ground and 3+ voltage, and the switching grid elements510-519 of this tube are connected to a conventional switch-ing circuit520 under the control of a further regulating flip-flop 525, which inturn receives the output pulses from discriminator output line 500. Theswitching grid elements 510- 519 are connected in the usual mannerthrough lines 526 and 527 so that the odd and even numbered switchinggrids are connected to lines 526 and 527', respectively.

A reset circuit 530 is connected to the beam deflecting spade elementsof tube 505 in the usual manner and receives an actuating pulse throughline 532 from the phase inverter output 490 for the purpose of resettingbeam switching tube 505 and directing the electron beam in that tube tothe first target element 540. All of the target element's 540-549 aretied through load resistors to the positive or Bi+ high voltage supply.The target element 547 is also connected to the output line 550' whichextends to spark control unit 172, and thus after beam switching tube505 has been reset a total of seven pulses must be received toregulating flip-flop 525 to advance the electron beam in tube 505 to thetarget element 547, resulting in an output to the spark control unit 172elfective to photograph the selected character. A reset pulse is alsodirected from output line 550 through line 552 to reset the flip-flopcircuits 410-416 to a desired state.

The operation of the system shown in FIG. 5 will be understood from thedescription of the previous embodiment, and therefore will not bediscussed in detail. It is understood that the discriminator circuits430436 are activated in sequence by the beam switching tube 458 andoperate to compare the binary code set up therein, digit by digit, fromthe photocells PC and P0 with the code set up in the selector flip-flops410-416 by the selector circuits 65. If the code indicia read coincides,digit by di-git, with the code in the selector flip-flops, then a totalof seven output pulses will pass to the regulating flip-flop 525, andbeam switching tube 505 will advance step by step until the electronbeam strikes the target element 547, resulting in a spark initiatingpulse through output line 550. If at any time during the reading of codeindicia between successive reset marks 35 there is a non-coincidence,then beam switching tube 505 will fall behind or out of phase with thesystem. There will be less than seven pulses fed to regulating flip-flop525 before the next following reset mark 35 causes a pulse to passthrough and gate 485, with resultant resetting of both beam switchingtubes 458 and 50-5 and also resetting of both regulating flip-flops 455and 525 without an output to the spark control circuits.

Thus, the operation of each of the above described systems is such thata code number set into the selector bank of flip-flop circuits iscompared, digit by digit, with each of the code indicia on the diskidentifying each of the characters, the disk being passed by thephotocell reading means to scan each code indicia or number on thematrix disk in sequence. This comparison may, especially in the case ofbinary code systems, be direct, ci.e., 1 for 1, or it may be acomparison of complements, i.e., the output signal may be given when thereading means locates the complement of the code number set into theselector. Such a result may be obtained, as well known in the art, bycausing the discriminator circuits to produce beam switching signalsonly when the complementary digits are sensed in the selector flip-flopand in the reading means.

In the above sense, therefore, the term coincidence as used herein maymean locating of like digits and code data or complementary digits andcode data. If there is a non-coincidence bet-ween any digit the systemfalls out of phase with the disk, for lack of a coincidence pulse, andno output to the spark control unit will be provided for that indicia.The system will be reset to scan the next indicia, and so on, and when acomplete digit by digit coincidence occurs, then an output pulse willpass immediately to the spark control unit to actuate the same andphotograph the character selected. These systems, therefore, can operateat a relatively high rate and are capable of photographing more than onecharacter for each cycle or revolution of the disk past the photocellreading means.

The present system is, of course, applicable to different types of codecomparing or coincidence seeking uses and is not confined to use inphototypesetting apparatus. The above described systems may, there-fore,be considered as exemplary for the purpose of disclosing typicalpractical applications of the principles of the present invention.

While the forms of apparatus herein described constitute preferredembodiments of the invention, it is to be understood that the inventionis not limited to these precise forms of apparatus, and that changes maybe made therein without departing from the scope of the invention whichis defined in the appended claims.

What is claimed is:

1. A character selection system \for phototypesetting apparatus,comprising a matrix having a plurality of characters defined thereon byparts of differential light transmitting ability, a controllableflashing light source of relatively high intensity and short duration,means mounting said matrix and said light source providing for relativemovement therebetween to align said light source with individualcharacters in predetermined succession, multi-digit code means on saidmatrix provided by a plurality of impulse generated means representingindi vidual digits and associated with and identifying each of saidcharacters, means for reading the code means for each said character indigitby-digit fashion during relative movement between said matrix andsaid light source, a selector including means for retaining temporarilycode data corresponding to a selected character, comparing means havinginputs from said reading means and said selector, means controlled bysaid comparing means for providing an output for every coincidencebetween digits of the retained code data and said code means, steppingmeans having a plurality of stages at least equal in number to thenumber of digits in said code means, said stepping means being connectedto said output and being responsive thereto for advancing one step foreach digit coincidence output, circuit means between said reading meansand said stepping means tending to advance said stepping means in phasewith the rate of digit-by-digit reading of the code means by saidreading means, and a connection between the last stage of said steppingmeans and said flashing light source for energiza-tion thereof when saidstepping means is advanced through a complete cycle indicativeofcoincidence between the retained code data and the code means for theselected character.

2. A character selection system for phototypesetting apparatus,comprising a matrix having a plurality of characters defined thereon byparts of differential light transmitting ability, a controllableflashing light source of relatively high intensity and short duration,means mounting said matrix and said light source providing forcontinuous relative movement therebetween to align said light sourcewith individual characters in predetermined succession, multi-digit codemeans on said matrix associated with and identifying each of saidcharacters, means for reading the code means for each said characterduring relative movement between said matrix and said light source, aselector including means for retaining temporarily code datacorresponding to a selected character, digit comparing means havinginputs from said reading means and said selector, means controlled bysaid comparing means for providing an output for every coincidencebetween digits of the retained code data and said code means, steppingmeans having a plurality of stages at least equal in number to thenumber of units in said code means, said stepping means being connectedto said output and being responsive thereto for advancing one step foreach coincidence output, means tending to advance said stepping means inphase with the rate at which said reading means scans the code means indigitby-digit fashion, a connection between the last stage of saidstepping means and said flashing light source for energization thereofwhen said stepping means is advanced through a complete cycle indicativeof coincidence between the retained code data and the code means for theselected character, and reset means connected to said stepping means forresetting thereof to the first stage upon reading of each code means foreach character.

3. A character selection system for phototypesetting apparatuscomprising a matrix having a plurality of characters defined thereon byparts of differential light transmitting ability, a controllableflashing light source of relatively high intensity and short duration,means mounting said matrix and said light source providing forcontinuous relative movement therebetween to align said light sourcewith individual characters in predetermined succession, binary numbercode means on said matrix associated with and identifying each of saidcharacters, each number of said code means being characterized by asuccession of pulse generating means arranged for "scanning in sequencealong with said relative movement between said light source and saidmatrix, each pulse generating means being located in one of twocharacteristic positions indicative of whether the digit it representsis a 1 or a 0, selector means for retaining binary code data identifyinga particular character on said matrix,

reading means for scanning each of the two possible positions for eachdigit of each number on said matrix, means mounting said reading meansfor relative movement with respect to said matrix for scanning the codenumbers carried on' said matrix along with relative movement betweensaid light source and said matrix, comparing means connected betweensaid reading means and said selector means for comparing digit by digitthe number of said selector means with the numbers on said matrix,stepping means in said comparing means and receiving a pulse for eachdigit in either position scanned by said reading means tending toadvance said stepping means in phase with said reading means, and meansconnected to said comparing means and to said light source producing anoutput signal to flash said light source only upon sensing of completecoincidence between all of the digits in the number retained in saidselector means and a number on said matrix.

4. A character selection system for phot'otypesetting apparatusincluding in combination a matrix bear-ing a plurality of characters, acontrollable flashing light source for illuminating chosen ones of saidcharacters in succession, and means mounting said matrix and said lightsource for relative movement to project said characters in successionalong a common optical path, said system comprising binary code indiciaon said matrix in predetermined relation to and identifying each of saidcharacters, said code indicia including a plurality of pulse generatingmeans located in one or the other of two paths adapted to be scannedduring said relative movement to generate in succession for each codeindicia digit pulses corresponding to a l or 0, reading means mounted toscan said pulse generating means and to transmit sep arate outputs forsaid 1 pulses and said 0 pulses, discriminator means connected toreceive said outputs from said reading means, a bank of bi-stableiiip-flop circuits corresponding in number to the number of digits inthe code indicia, selector means connected to said flip-ilop for settingthe same individually to states corresponding to the digits in aselected code number, normally inactive circuit means between each ofsaid flip-flops and said discriminator means for conveying thereto thestate of the individual flip-flops, switching means operativelyassociated with said normally inactive circuit means for activating thesame individually in sequence to compare the state of each saidflip-flop with a corresponding digit pulse, circuit means responsive tothe rate of operation of said reading means and connected to saidswitching means tending to advance said switching means in phase withthe rate of operation of said reading means, an output signal connectionfrom said discriminator means to said switching means advancing the samefrom one normally inactive circuit means to the next in response to acoincidence between a digit pulse and the state of the correspondingflip-flop, and means responsive to successive activation of all saidnormally inactive circuit means for flashing said light source.

5. Apparatus for determining the location of a selected binary number ona member having a plurality of such numbers arranged in successionthereon, each number being characterized by a succession of pulsegenerating means arranged for scanning in sequence, each pulsegenerating means being locatedin one of two characteristic positionsindicative of whether the digit it represents is a "1 or a 0, selectormeans for retaining a binary number to be located on said member,reading means for scanning each number on said member digit by digit,means mounting said reading means and said member for scanning thenumbers carried on said member, comparing means connected between saidreading means and said selector means for comparing digit by digit thenumher in said selector means with the numbers on said memher, saidcomparing means producing an output signal for each coincidence betweena digit of the number in said selector means and a digit of the numberbeing scanned, stepping means having a plurality of stages at leastequal in number to the number of digits in the binary numbers on saidmember, means connecting said stepping means to said comparing meansadvancing said stepping means one step for each digit coincidence signalfrom said comparing means, circuit means connected between said readingmeans and said stepping means tending to advance said stepping means onestep for each digit read by said reading means, output means connectedto said stepping means for transmitting an output signal therefromindicative of a complete coincidence between all of the digits of thenumber in said selector means with all of the digits of a number on saidmember, and means for resetting said comparing means after scanning alldigits of a number without a complete coincidence.

6. Apparatus for determining the location of a selected binary number ona member having a plurality of such numbers arranged in successionthereon, each numher being characterized by a succession of pulsegenerating means arranged for scanning in sequence, each pulsegenerating means being located in one of two characteristic positionsindicative of whether the digit it represents is a l or a O, selectormeans for retaining a binary number to be located on said member,reading means for scanning each number on said member digit by digit,means mounting said reading means and said member for scanning thenumbers carried on said member, comparing means connected between saidreading means and said selector means for comparing digit by digit thenumber in said selector means with the numbers on said member, saidcomparing means producing an output signal for each coincidence betweena digit of the number in said selector means and a digit of the numberbeing scanned, stepping means having a plurality of stages at leastequal in number to the number of digits in the binary numbers on saidmember, means connecting said stepping means to said comparing meansadvancing said stepping means one step for each digit coincidence signalfrom said comparing means, circuit means connected between said readingmeans and said stepping means tending to advance said stepping means onestep for each digit read by said reading means, output means connectedto said stepping means for transmitting an output signal therefromindicative of a complete coincidence between all of the digits of thenumber in said selector means with all of the digits of a number on saidmember, and reset means connected between said stepping means and saidselector means for erasing the number retained in said selector meansonce the number has been located on said memher.

7. Apparatus for determining the location of a selected binary number ona member having a plurality of such numbers arranged in successionthereon, each number being characterized by a succession of pulsegenerating means arranged for scanning in sequence, each pulsegenerating means being located in one of two characteristic positionsindicative of whether the digit it represents is a 1 or a 0, selectormeans for retaining a binary number to be located on said member,reading means for scanning each number on said member digit by digit,means mounting said reading means and said member for continuouslyscanning the numbers carried on said member, comparing means connectedbetween said reading means and said selector means for comparing digitby digit the number in said selector means with the numbers on saidmember, said comparing means producing an output signal for eachcoincidence between a digit of the number in said selector means and adigit of the number being scanned, stepping means having a plurality ofstages at least equal in number to the number of digits in the binarynumbers on said member, means connecting said stepping means to saidcomparing means advancing said stepping means one step for each digitcoincidence signal {from said comparing means, circuit means connectedbetween said reading means and said stepping means tending to advancesaid stepping means one step for each digit read by'said reading means,output means connected to said stepping means for transmitting an outputsignal therefrom indicative of a complete coincidence between all of thedigits of the number in said selector means with all of the digits of anumber on said member, means for resetting said comparing means afterscanning all digits of a number without a complete coincidence, andreset means connected between said stepping means and said selectormeans for erasing the number retained in said selector means once thenumber has been located on said member.

8. Apparatus "for locating a selected binary number on a member bearinga plurality of different binary code indicia, said code indiciaincluding a plurality of pulse generating means located in one or theother of two paths on said member, said pulse generating means beingadapted to generate in succession for each code indicia digit pulsescorresponding to a l or a 0, reading means mounted to scan said pulsegenerating means and to transmit separate outputs for said 1 pulses andsaid 0 pulses, discriminator means connected to receive said outputsfrom said reading means, a bank of bi-stable flipfiop circuitscorresponding in number to the number of digits in the code indicia,selector means connected to said flip-flops for setting the sameindividually to states corresponding to the digits in a selected binarycode number, normally inactive circuit means between each of saidflip-flops and said discriminator means for conveying thereto the stateof the individual flip-flops, switching means operatively associatedWith said normally inactive circuit means for activating the sameindividually in sequence to compare the state of each said flip-flopwith a corresponding digit pulse, circuit means connected between saidreading means and said switching means tending to advance said switchingmeans once for each scanning of a single digit by said reading means, anoutput signal connection from said discriminator means to said switchingmeans for advancing the same from one normally inactive circuit means tothe next in response to a coincidence between a digit pulse and thestate of the corresponding flip-flop, and means responsive to successiveactivation of all said normally inactive circuit means providing. anoutput signal indicative of complete coincidence between the selectedcode number and code indicia on said member.

References Cited in the file of this patent UNITED STATES PATENTS2,641,696 Woolard June 9, 1953 2,749,533 Daniels June 5, 1956 2,775,172Higgonnet et al Dec. 25, 1956 2,782,398 West et a1. Feb. '19, 19572,784,397 Branson Mar. 5, 1957 2,785,388 McWhirter Mar. 12, 19572,842,663 Eckert July 8, 1958 2,865,270 Higgonnet Dec. 23, 19582,876,687 Higgonnet Mar. 10, 1959 2,923,215 Corrado Feb. 2, 1960

